Switch operating mechanism



July 15, 1958 Q THEUN 2,842,981

SWITCH OPERATING MECHANISM Filed July 29, 1955 5 Sheets-Sheet 1 Iig-l I! i. f" X 3, C, i l I n I INVENTOR.

CARL F. THELIN BY $441M- ATTORNEY July 15, 1958 C. F. THELIN SWITCH OPERATING MECHANISM 5 Sheets-Sheet 2 Filed July 29. 1955 INVENTOR.

CARL F. THELIN ,QMW

ATTORNEY July 15, 1958 c. F. THELIN I 2,842,981

SWITCH OPERATING MECHANISM Filed July 29, 1955 5 Sheets-Sheet 3 INVENTOR.

CARL F. THELIN ATTORNEY SWKTQIH @PERATEFIG Pvi EiIHA-lNESlt i Carl F. Thelin, Detroit, Mich, assignor to McGraw- Edison Company, a corporation Application Early 29, 1955, Serial No. 525,180

Claims. (Ci. 74-55%) This invention relates to mechanism for manually operating electric switches or other devices from a remote station. More particularly, the instant invention pertains to a torsional operating handle which coacts with a latch for selectively restraining the handle in definite angular positions.

In electric power systems electric switches are frequently mounted a considerable height above the ground on wood poles or other structures which support electrically live conductors at safe distances above areas traversed by human beings. To avoid having a lineman ascend the switch supporting structure when he desires to perform a switching operation a shaft is extended from the switches to a station more safe and accessible at ground level.

It is an object of the instant invention to provide a mechanism for controlling the position of electric switches at safely remote distances.

It is a further object of this invention to provide a latch which registers with suitable angular limiting stops associated with the handle at various positions of the latters angular swing.

A still further object is to provide a latch which is self releasing upon initiation of manual effort commencing a rotational operation and self-engaging at the termination of such operation.

Another object is to provide stopswhich are angularly adjustable for attaining a precisely controlled swing angle.

Still another object of this invention is to provide an operating mechanism which may be adjustably established at the most convenient height above ground level for most effective manual operation.

Another object is to provide a torsional operating mechanism in simplified form which is easy to assemble, install, and operate and is substantially tamper proof during the interim between operations.

Stated in general terms, the invention comprises a vertical shaft to which there is fastened an adapter socketed for receiving a removable handle through which operating force is applied. A clamp is secured to the shaft and provided with stops which project radially into the path of a suitable latch plate which coacts with the stops. When in inactive position, the operating handle may be removed from its adapter and deposited in a socket adjacent the latch for urging the latch against the stops. Removal of the handle from the adapter, however, and mere initiation of manual effort tending to rotate the shaft, causes the latch plate to pivot freely on a suitable knife edge out of the path of the stops under the influence of its own geometrically displaced center of gravity. During angular movement of the handle, the latchplate is disposed against the stops in such manner that it automatically drops into latched position at completion of the angular swing.

A preferred embodiment of the invention is illustrated in the drawings in which:

Fig. 1 is an elcvational view of the automatic latch and operating mechanism, forming'the subject of the in- 2,842,981 Patented July 15, 1958 2 stant invention, in conjunction with an axially rotatable insulator such as that employed in an air disconnect switch;

Fig. 2 represents the assembly of Fig. 1, partly in section on a line corresponding with 2-2 in Fig. 4, showing the latch in released position and the operating mechanism in a first position;

Fig. 3 illustrates the position of the various components immediately after rotational movement of the operating mechanism has been initiated;

Fig. 4 is a plan view partially in section looking in the direction of the arrows on the line 44 of Fig. 1;

Fig. 5 is a plan view illustrating the operating mechanism in a second latched position; and i Fig. 6 is an elevational view of a latch plate such as employed in the structure represented by the preceding figures.

For a more specific description of the invention reference is made to Fig. 1 where is shown an insulator 1, such as may support and transmit operating torque to an air disconnect switch (not shown). Insulator 1 is supported and journaled for rotation on a bearing structure designated generally by the reference numeral 2. The bearing structure is in turn supported on a suitable channel 3 or any other structural member located a considerable height above ground level. Torsional force is transmtited from an operating station near ground level to insulator 1 through the agency of tubular shafts 4i and 5 extending vertically and coupled by any suitable means (not shown).

More detail regarding construction of switches to which the present invention may be adapted will be seen in the copending application of Thorsten A. Fjellstedt, Serial No. 409,694, filed February 11, 1954, entitled Switch Group Operating Mechanism and assigned to the assignee of the instant application.

By reference to Figs. 1 and 2, it will be observed that shaft 5 has fastened to it a clamp 7 composed of two identical split sections held in compressive clamping relation by means of carriage bolts 8. To assure that clamp 7 will not slip relative to shaft 5 the former is provided with a radially inwardly extending integral key 10 which engages a suitable longitudinal keyway 11 in the form of a groove impressed along the length of shaft 5. This arrangement eliminates the necessity of cutting shaft 5 to a precise length, for it is possible by merely loosening carriage bolts 8, to permit the shaft to extend through clamp 7 if the shaft is too long. Thus, it is not necessary to violate the protective galvanizing coating by sawing off the shaft during installation in order to accommodate it to a particular placement of the coupling 7. Rather, shaft 5 may beallowed to extend through the coupling any reasonable distance so that the height of coupling 7 and its associated parts may be established without regard for the length of the shaft.

Each half of clamp 7 terminates at its upper portion in a radially extending flange 9. A serrated ring 14 surrounds shaft 5 concentrically and bears directly on flange 9. Ring Eldis right angular in cross section (see Fig. 2) and has its upper face provided with serrations 15 which are angularly spaced from each other in five degree intervals. Serrations 15 are presented to and register with corresponding opposed serrations on an adapter ring '16.

Adapter ring 16 surrounds the axially extending portion of flange ring 14 and also has extending from it an integral adapted socket 17 into which a pipe handle 20 may be placed or removed. In the fragmentary portion of Fig. 2 it will be noted that adapter 17 has projecting inwardly from it a lug 21 which registers with a corresponding hole in handle 2.0. Registry of the lug assures that bushing, shaft projects.

6. the handle is placed fully into adapter 17 and that inadvertent removal of handle 20 will be precluded.

From the description given thus far it will be evident that manual force exerted on handle 22 is transmitted to shaft 5 through the agency of coupling clamp 7. It

will also be noted that the construction is such, by reason of the serrations, as to facilitate convenient angular adjustment between clamp '7 and handle adapter 17.

In the sectioned portion of Fig. 2 it is evident that flanged ring 14, clamp flange 9, and the serrated adapter ring 16 integral with adapter 17 are held tightly together by means of a plurality of equispaced round headed bolts 23. A portion of the head of each bolt 23 bears on flanged ring 14 and another portion bears on superposed segmental stop rings 22 and 24, the purpose of which will be explained hereinafter, in tight clamping rotation. Thus, it is apparent that stop rings 22 and 24 may be adjusted angularly about the axis of shaft 5 by loosening bolts 23 and sliding the rings around, the rings then being clamped permanently in the desired position.

The configuration of stop rings 22 and 24- can be seen most clearly by reference to Figs. 4 and 5, where it is apparent that they are provided with radially extending segmental portions defined by outer arcuate peripheries 25 and 25a, and a pair of remote circumferentially spaced stop edges 26 and 27, respectively. Although two of the stop rings are shown in the illustrative embodiment, it should be appreciated that under certain circumstances only one stop ring 24 may be necessary and under other circumstances, where it is desired to swing handle 20 through a greater are, more than two such rings may be desirable.

The segmental stops together with their stop edges 26 and 27, indicating the extremities of the swing angle, are arranged to coact with a latch plate designed generally by the reference character 30, shown in detail in Fig. 6. Inspecting Fig. 1, however, in conjunction with Fig. 4, it will be noted that for the corresponding positions of handle 20 there represented, stop edge 26 bears in compressive relation against a side of latch plate 30. Consequently, in Fig. 4, latch plate is in position to prevent clockwise rotation of handle 20. In Fig. 5, however, handle 20 has been rotated to a second angular position so that stop edge 27 bears against an opposite edge of latch plate 30, thereby preventing counterclockwise rotation of handle 20. The circumferential spacing of stop edges 26 and 27, obtained through adjustment of plates 22 and 24, determines the total angular swing of handle 20.

Where, in order to obtain a swing angle considerably greater than that for which the structure shown is arranged, it follows that the stop edges 26 and 27' must be spaced at such distance that it becomes possible for latch plate 30 to catch in between them, it is advisable to use an additional or third stop ring in order that outer arcuate peripheries 25 and 2511 present a continuous smooth surface to latch 30 between the limits 26 and 27 This may be accomplished by merely superposing an additional stop ring on the others and clamping it by means of bolts 23.

Where as lesser swing angle of handle 20 is desired, it is, of course, possible to use only one stop ring and accordingly, a single segment. The angle of swing is greater in all cases than indicated by the total length of arcuate peripheries 25 and 25a, the swing angle being equal to the total angular distance between stops 26 and 27 plus the angle subtended by the width of latch plate 30.

The lower end of tubular shaft 5 is journaled in a bronze bushing carried in the lower part of a substantially U-shaped mounting bracket 36, through which Bracket 36 is provided with holes 37 for fastening it at a convenient height above ground level against a wood transmission pole or any other structure associated with the mounting of electrical switches.

In Fig. 1 it will be observed that when the operating handle 20 is not in use it may be stored in bracket 36 by passing it through holes 38 and 39 provided for that purpose and also for accommodating latch plate 35). When in stored position in the socket defined by holes 38 and 3, handle 20 is supported on a counter balancing bent back portion 31 of latch plate 30. In Fig. 1, handle 20, being closely confined in holes 38 and 39, bears tightly against latch plate 30 so that the latter is positively restrained against departure from the path of stop edge 26. When handle 20 is stored as indicated by the solid lines representing it in Fig. 1, a lock or pin may be passed through a hole 19 in its free end to prevent its removal, and unauthorized operation of the switches.

it will be observed in Fig. 1 that the end of latch 30 having the right angular bent portion 31 extends through bracket 36 but that the latch 30 itself is prevented from falling out by laterally extending shoulders 33 formed in the longitudinal margins of latch 30. These shoulders 33 are (see Fig. 6) wider than hole 39 and they terminate in knife or pivot edges 32. Thus, it is evident from inspection of Fig. 2 that removal of handle 20 may enable latch 30 to pivot on edges 32 out of the path of stop edge 26. However, in reality, mere removal of handle 20 is not sufficient to cause latch 30 to pivot as aforesaid because there is usually and preferably considerable counter-torque or back-lash in tubular shaft 5 causing stop edges 26 and 27 to remain in the path of the latch. It will be explained in ensuing paragraphs how advantage is taken of this back-lash and how it augments operation of the mechanism.

The sequence of events associated with manual operation of the mechanism described above will now be explained in detail in conjunction with the drawings. In

Fig. l the components may be termed as in inactive position with handle 20 disposed in the sockets and its periphery bearing against latch plate 30. Latch plate 30 in turn stands firmly in the path of the leading stop edge 26 (see particularly Fig. 4). Recall that it is assumed that there is some back-lash in shaft 5 so that mere removal of handle 20 as in Fig. 4 will not, without more, permit latch 30 to pivot backward on its knife edge 32.

When it is desired to actuate mechanism from the first position shown in Fig. l to a second position represented by Fig. 5, handle 20 is deposited in adapter 17, as indicated by the dashed lines in Fig. 1 and the solid lines in Fig. 4. Then, although the final position desired is in a clockwise direction of rotation, a force is exerted against handle 20 in a counterclockwise direction. This frees latch 30 from restraint by leading stop edge 26 so that the latch may pivot backwardly on its knife edge 32 under the influence of the counter balancing eifect of end 31, thus clearing the path for the stop segments to execute clockwise rotation.

Prior to commencement of clockwise rotation, the knife edges 32 are slid away from the axis of shaft 5 as indicated in Fig. 3. Under the influence of the backlash in shaft 5, leading stop edge 26 will rotate slightly in a clockwise direction so that latch 30, which is now inclined toward shaft 5 (see Fig. 3) will bear against the arcuate periphery 25 on the stop segments. Consequently, when handle 20 is swung to the position of Fig. 5, latch 30 will fall inwardly toward the axis of shaft 5 and catch adjacent trailing stop edge 27.

It is usually advisable that some back-lash be accumulated in shaft 5 before handle 20 has executed its full swing. This allows latch 30 in its inclined position of Figs. 3 and 5 to eifectively restrain stop edge 27. Subsequently, handle 20 may be removed from its adapter 17 and forcefully urged through hole 38 against latch plate 30 until the handle strikes end 31 thereof. This causes latch plate 30 to be restored to a perfectly vertical position as it was initially in Fig. 1. Restoration of handle 20 to its socket permits locking of the mechanism against hands on handle Zll after latch 30 has been placed in the inclined position of Fig. 3. This is a particularly important safety feature since handle is secured firmly in adapter 17 and any sudden yielding of the load being actuated does not cause the operator to lose his balance nor is it possible for the handle to suddenly yield in a vertical direction. Moreover, where electric switches are being operated by the mechanism it is highly desirable that they be urged to a positive open or closed position. This positive action is assured by the instant invention because of the latch 36 storing energy in the form of back-lash in shaft 5.

It is evident that the mechanism is adjustable to almost any angle of swing short of complete circular rotation. Such adjustment is accomplished, as indicated hereinbefore, by two distinct methods: The first, being by adjusting the relationship between the serrated flange ring 14 and its cooperating serrated adapter ring 16; the second, being adjustment of the spacing between stop edges 26 and 27 by sliding them circumferentially about shaft after loosening of round head bolts 23. Where greater spacing of stop edges 26 and 27 is desired so that the circumferential space between edges 26' and 27 is increased in excess of the width of latch plate 3t it is preferable that three or more stop rings be used so that a continuous arcuate edge 25, a is presented to the latch plate and so that it will not fall between the space defined by edges 26' and 27' during swinging movement of handle 20.

From the foregoing description it will be evident that the novel operating mechanism and latch are conveniently and automatically releasable prior to commencement of an operation and that the device is self latching at completion of such operation. Moreover, it is evident that all of the parts are inseparable subsequent to installation so that none of them can be lost during operation. It is further more evident that the mechanism and latch may be conveniently operated by a lineman who is wearing heavy insulating gloves as is often the case, since it is not necessary to handle any delicate parts such as locking pins and the like during operation. The mechanism is also seen to be highly versatile insofar as establishing its angle of swing is concerned and conveniently placeable at any suitable height above ground level fo most convenient manualoperation.

Although only a preferred form of the invention has been illustrated, it is realized that those versed in the art may, using the disclosure herein as a basis, design various modifications which resemble that disclosed. However, it should be understood that the invention is limited only by the spirit and scope of the claims which follow. M

It is claimed:

1. Torsional operating mechanism comprising, a shaft axially rotatable to first and second angular latched positions, a plurality of superposed stop segments projecting radially from said shaft and clampingly held thereon for angular adjustment about the axis of the shaft, each stop segment having stop means and an arcuate peripheral margin, said stop means being spaced circumferentially and said arcuate margins being adjacent and presenting a substantially continuous periphery, a latch plate generally in parallelism with the shaft and disposed in the circumferential path of said segments and selectively abutting alternate stop means in compressive relation when the shaft is in said first and second angular latched positions, respectively, support means for said latch, said latch including a knife edge slidable and pivotable on said support means radially of said segments, said latch having a first pivot position on said support means for swinging at an angle out of the path of said stop means whereupon said shaft may be turned toward its second angular position and said latch having a second pivot position for swinging at an angle into the path of said stop means when said shaft attains its second angular position.

2. Torsional operating mechanism comprising a shaft axially rotatable to first and second angular positions, circumferentially spaced stop means projecting radially from and rotatable with said shaft, a U-shaped bracket having spaced legs projecting toward said shaft and with said shaft journaled in one leg thereof, said bracket having apertures in each leg with their axes in substantial parallelism with the axis of said shaft, said stop means projecting into and rotating transversely to the axis of the apertures, a latch plate having laterally extending pivot edges supported slidably on one of said legs and having a portion extending through one of said apertures terminating in an angular bend directed transversely of the common axis of said apertures, rod means disposable through said apertures in juxtaposition to said latch plate on a side thereof opposite said shaft and fully occupying said apertures and in endwise bearing relation against said angular bend, whereby said rod means restrains said latch platein the path of said stop means when they are in said juxtaposition and removal of said rod means from said apertures permits said latch plate to mOVe from the path of said stop means for rotation of said shaft.

3. Torsional operating mechanism comprising a shaft axially rotatable to first and second angular latched positions, an arcuate segment projecting radially from the shaft for rotation therewith, said segment having radially directed stop edges spaced from each other through an arc, an elongated plate-like latch generally disposed parallel with the shaft axis when said shaft is latched in either angular position while at the same time being in the path of one of said stop edges, pivot means carried by said latch intermediate its ends, substantially flat bracket means slidably supporting said latch on its pivot means, said latch being pivotable on its pivot means when in one pivot position from parallelism with said shaft axis to an angle therewith clear of said segment and also being pivotable at an opposite angle when in another pivot position whereupon the latch bears on said segment toward the axis of rotation, whereby rotation of said shaft in a direction opposite from the second angular position allows said latch to pivot in its first pivot position out of the path of, one stop edge whereupon said latch may he slid to its second pivot position for re-engaging said other stop edge when said shaft is rotated in a direction toward second angular position.

4. The invention according to claim 3 including a clamp assembly secured to said shaft, handle means clampingly releasably secured to said clamp assembly for angular adjustment around the shaft axis and supporting said segment, and means holding said segment and said handle means jointly to said clamp assembly.

5. Torsional operating mechanism comprising a shaft axially rotatable to first and second angular latched positions, a segment having an arcuate periphery and edges defining stop means projecting radially from and rotatable with the shaft, a U-shaped bracket means having apertured legs spaced in planes transverse to the shaft, a latch plate disposed for movement in the embrace of said apertures into and out of latching engagement with the stop means, knife-edge means carried by the latch plate and slidably and pivotably supported on one of said legs adjacent the margin of one aperture, said latch plate also having an extension means transverse to the axis of said 7 apertures, rod means insertable through and shbstantially References Cited in the file of this patent fully occupying the apertures and being intercepted by UNITED STATES PATENTS said extension means for preventing movement of said 795 670 Whitehorne July 25 1905 latch plate only when the shaft is in either of its angular 5 1,077: 487 Miller' No I 1913 positions and said latch plate is in the path of said stop 1,078,875 Pyle 18 1913 means. 2,698,492 Justice Jan. 4, 1955 

